The protein array technology allows the screening of biochemical activities or binding abilities of hundreds or thousands of protein samples in parallel. After synthesis and purification by high-throughput methodologies, the proteins are printed onto the chip by using an instrument (micro-arrayer) that is capable of spotting liquid samples in a reproducible manner onto a planar support. The ordered protein array can then be probed with labelled molecules to identify proteins that bind to the bait. [ http://www.ncbi.nlm.nih.gov/pubmed/12067604 http://www.ncbi.nlm.nih.gov/pubmed/10976071 ]